wasting our time in this cave. Phew! How cold it is in here!"

"And well it might be," laughed Dick. "Do you see that mass just
ahead of us?"

"What is it?" asked Dan. "Flash the light on it."

"Come over and look at it," Dick went on. "No one could live
in this cold place. It is chilling me to the bone, just to stand
here. And now you see why that little trickle of water keeps
moving out through the mouth of the cave. Fellows, we're in one
of nature's icehouses."

"But we're not after ice," Dave protested.

"We won't turn down ice in the wilderness, when we can find it
in July," Dick rejoined.

"Not much!" answered practical Tom Reade. "Why, fellows, ice is
just what we need at the camp. Let's get a closer look at it
and make plans for an ice-box over at the camp."

"But I want to follow that man of mystery," protested Dave.

"Go ahead, David, little giant," Dick laughed. "We won't stop
you. But we've lost our man of mystery, anyway, and this cave
contains something that we really do want. Tom, you're the
mathematician of the party. How much ice is there here?"

"If I could see better I could tell you better," sniffed Reade.